The capture and storage of images using digital techniques comprises a well understood area of endeavor. This holds true for both still images and video images. Such digital content can require considerable storage and/or transmission resources. As a result, the encoding of such image content in order to consume reduced storage/transmission resources also comprises a well understood area of practice. Various discrete cosine transformation-based encoding approaches exist, for example, to achieve such results.
In many such approaches, source video frames are divided and encoded as a series of rectangular macroblocks. When subsequently decoded, the pixels as correspond to these macroblocks are typically derived either from discrete cosine transform-encoded texture data (often known as Intra-encoding) or from a combination of motion compensation information as applied to previously decoded pixels coupled with a residual discrete cosine transform-encoded texture data (which may be either, for example, Inter or predictive encoding).
Such a hybrid encoding scheme can reliably produce a reasonably accurate reconstruction of the original source video frame. In many cases, in fact, the reconstruction process is perfectly defined by a corresponding standard (in the sense that every decoder complying with a given compression standard will reproduce the same pixel-for-pixel output when fed a same compressed bitstream input). When dealing with errored input, however, the decoding process can introduce ambiguity. This occurs in substantial part due to a lack of standardization regarding the handling of errored content (which comprises, for example, corrupted and/or missing pixel information).
For many application purposes, such ambiguity does not necessarily present a problem. It simply means that different decoder designers and manufacturers have an opportunity to differentiate their offerings from one another in this regard, often to the benefit of the consumer. The applicant has determined, however, that there are other application settings when such ambiguity comprises an undesired circumstance. Public safety application settings, for example, do not necessarily benefit from a portrayal of ambiguous image content. Tactical decision making will benefit more, for example, from understanding what is assuredly real in a given image and what is potentially suspect. The same may hold true when seeking to instantiate the evidentiary value of a given image for use in a courtroom. The applicant has therefore recognized and determined that present ambiguity introduced by today's image decoding processes when processing errored image content can accordingly be viewed as being distinctly unhelpful in such application settings.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of various embodiments. In addition, the description and drawings do not necessarily require the order illustrated. Apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the various embodiments so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein. Thus, it will be appreciated that for simplicity and clarity of illustration, common and well-understood elements that are useful or necessary in a commercially feasible embodiment may not be depicted in order to facilitate a less obstructed view of these various embodiments.